Conventional earth leakage breakers are used as a component of an electric power distribution system, to prevent fire due to over-current, over-voltage or overload of electricity, in which an over-current, over-voltage or overload state of electricity is detected. However, recent studies have reported that most electrical fires are not caused by occurrence of an electric current leakage or overload, but are actually caused by occurrence of an arc. Since 2002 in the U.S.A., an arc fault circuit interrupter (AFCI) has been required under many building codes.
An arc fault circuit interrupter (AFCI) generally includes a mechanical unit, a sensor unit, and an electronic circuit unit. An arc generator is needed to test the electronic circuit unit among these components. Conventionally, a mechanical arc generator which generates arc by mechanical and electrical contact of blades or electric rods is usually used. Here, the generated arc wave is not a general sinusoidal wave but is of various wave forms according to various arcs.
That is, an arc is generated using an electric spark that occurs due to mechanical and electrical contact of the blades or electric rods. The generated arc is applied as an input of an arc detection circuit which is provided inside of the arc fault circuit interrupter (AFCI) to thereby test the AFCI's operational state.
However, the conventional mechanical arc generator has difficulty in performing correct simulation because the arc wave is irregularly generated and thus the AFCI's test condition is changed every time. Thus, there is a need for an improved arc wave generator for testing AFCIs.